Re: [PATCH v2 2/2] KVM:SVM: Update cr3_lm_rsvd_bits for AMD SEV guests

[Paolo Bonzini]

On 12/11/20 23:18, Babu Moger wrote:
> +	/*
> +	 * For sev guests, update the cr3_lm_rsvd_bits to mask the memory
> +	 * encryption bit from reserved bits
> +	 */

Say why in the comment, don't repeat what the code already says (ok, 
technically the code didn't say that CPUID[0x8000001F].ebx hosts the 
memory encryption bit).  I changed this to:

/* For sev guests, the memory encryption bit is not reserved in CR3.  */

and queued the patches,

Paolo

> +	if (sev_guest(vcpu->kvm)) {
> +		best = kvm_find_cpuid_entry(vcpu, 0x8000001F, 0);
> +		if (best)
> +			vcpu->arch.cr3_lm_rsvd_bits &= ~(1UL << (best->ebx & 0x3f));
> +	}
> +